Isothermic protective boot

ABSTRACT

An isothermic protective boot designed particularly for patients with arterial disease. The boot has a complete inner lining and outer cover of a soft, non-allergenic material, a double layer of a soft, flexible, compressible isothermic protective material between the outer cover and inner lining, and a body of flexible, compressible weight-bearing material at the back of the boot in a position to extend along the heel cord and lower aspect of the calf of the patient&#39;s leg.

This invention relates generally to protective boots and refers moreparticularly to an isothermic protective boot for bedridden patientswith arterial disease.

BACKGROUND AND SUMMARY

Patients with severely ischemic legs may have, in addition to lowperfusion of their feet, vasoconstriction of skin vessels which renderstheir skin more susceptible to otherwise trivial trauma (decubitus).This peripheral vasoconstriction can often be abolished by surgical orpharmacological sympathectomy. It can also be avoided with bulkyisothermic dressings which promote autonomic dilation of skin vessels.

When lying in bed a good portion of the weight of the extremity of thepatient rests on the posterior aspect of the heel. Patients withischemic extremities are prone to develop ulcerations in this pressurepoint which, once established, nearly always necessitates an amputationunless an arterial reconstruction is possible.

In patients with severely ischemic legs other trivial injuries may occurwith the limited ambulation which is allowed to them. A small abrasioncaused by contact with the edge of the bed or chair may result in anon-healing ulceration with catastrophic results.

One protective appliance that has been used in the past consists of acylinder of synthetic or natural cotton which is wrapped around the footand lower leg and is held in place by a tubular elastic net. However,removal and reapplication for inspection and care is awkward and afterminimal ambulation they must be discarded and replaced.

A general object of the present invention is to provide a boot whichgives improved protection for the foot and lower leg of a patient whomay, for example, be suffering from arterial disease.

The boot of the present invention has the following characteristics:

(1) It may be worn by patients in bed and also allows limited ambulation(to bathroom, at bedside, etc.).

(2) It protects the foot from trauma.

(3) It is isothermic and, to the extent possible, prevents heat lossfrom the foot, while at the same time permitting breathing andevaporation of sweat from the skin surface.

(4) It distributes the weight of the extremity over a large surfacearea. The design takes into consideration the fact that the weightbearing surface when the patient is lying down will not be at the bottomof the heel but rather over the heel cord and the lower aspect of thecalf on a much wider area than that upon which the foot would normallyrest. By transferring the weight of the extremity to a much larger area,the effective pressure insult on the skin is diminished.

(5) It is soft and will reach to the junction of the lower and middlethird of the calf.

(6) Because it is intended for use by individuals who oftentimes haveinfection or ulcerations in the foot, the boot is designed to bedisposable.

(7) It is not so costly that it cannot be discarded after use by apatient in the hospital.

(8) It allows for easy opening of the boot for inspection and carepurposes.

(9) It is free of hard surfaces or corners on the outer surface to avoidinjury to the other extremity of the patient since it will be used inmost cases by bedridden patients.

These and other objects will become more apparent as the followingdescription proceeds, especially when considered with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a lamination from which the main body portionof the boot of this invention is formed.

FIG. 2 is an edge view of FIG. 1 looking in the direction of the arrow2.

FIG. 3 is a detail view in elevation of an insert or body ofweight-bearing material for the boot.

FIG. 4 is a side view of the insert.

FIG. 5 is a bottom view of the insert.

FIG. 6 is a view of the lamination of FIG. 1 after the upper half hasbeen folded over the lower half.

FIG. 7 is a detail view in elevation of the insole of the boot.

FIG. 8 is a sectional view taken on the line 8--8 in FIG. 7.

FIG. 9 is a bottom plan view of the boot.

FIG. 10 is a perspective view of the boot.

FIG. 11 is a sectional view taken on the line 11--11 in FIG. 10.

FIG. 12 is a sectional view taken on the line 12--12 in FIG. 11.

DETAILED DESCRIPTION

Referring now more particularly to the drawings, the boot is constructedessentially of four parts, namely a main body portion 10, a bottom treadportion 12, an insole 14 and a body or insert 16 of weight-bearingmaterial.

The main body portion 10 is formed initially as a flat lamination 18(FIG. 1) and is composed of a sheet 20 of relatively soft, flexible,compressible, protective, cushion material and a flexible cover sheet 22secured to one side of the sheet 20. Both sheets are cut to theconfiguration shown in FIG. 1.

The sheet 20 is formed of isothermic heat-insulating material which ispreferably porous and prevents, as much as possible, the dissipation ofheat from the foot, while at the same time permitting breathing andevaporation of sweat from the skin surface. While expanded polyurethaneis preferred as the material of the sheet 20, other materials such, forexample, as natural foam rubber or any suitable synthetic flexible foam,either open or closed cell, may be used. As more fully describedhereinafter, the sheet 22 will provide a cover for both the inside andoutside of the boot and should be relatively soft, gentle andnon-allergenic so as not to irritate the skin of the foot and lower legprotected by the boot nor to injure the other extremity of a patient whoin most cases will be bedridden. The sheet 22 may, for example, be madeof paper, non-woven urethane, cotton or any natural or syntheticmaterial which is sufficiently gentle and non-abrasive. The sheets 20and 22 may be heat-bonded together or adhered to one another by asuitable adhesive.

The flat lamination 18 is composed of two portions 24 and 26 which areidentical in configuration and joined along an imaginary fold lineindicated at 28. These portions 24 and 26 are folded together along thefold line 28 with the cover sheet 22 on the outside of the fold. Theco-extending side edges are stitched together where indicated at 30(FIG. 6), the portions on either side of an imaginary central verticalline in FIG. 6 are brought toward one another and stitched together atthe toe of the boot where indicated at 32 to form the main body portion10 composed of a leg-receiving part 34 and the top and sides of thefoot-receiving part 36 (see FIG. 10). The entire main body portion 10 iscovered on the inside and outside by the cover sheet 22 and has twolayers 37 of cushion material 20 within. The main body portion 10 iscompleted by the application of ties 38 to the stitched edges 30 eitherbefore or after stitching of the toe at 32. Such ties may also beapplied by stitching or by any other suitable means.

The body 16 of weight-bearing material is of the configuration bestshown in FIGS. 3-5. It may be formed of the same material as sheet 20and, while it is both flexible and compressible, it is firmer, that isnot as easily compressed, as the sheet 20. The body 16 has a rectangularcentral portion 40 separated from lower wing portions 42 by grooves 44.The body 16 is disposed between the two layers 37 of cushion material inthe position shown in FIG. 6 (also as shown in phantom lines in FIG. 1).No special securing means are required to retain the body 16 in place.In this position, the central portion 40 of body 16 is disposed uprightand midway between the opposite stitched edges 30, with the wingportions 42 projecting laterally outwardly from the lower part of thecentral portion 40. The central portion 40 is at the back of the bootoverlapping the foot and leg-receiving portions (see FIG. 11) inposition to extend along the heel cord of the patient. The wing portionsfold forwardly along grooves 44 when the sides of the main body portion10 are brought together and stitched at the toe (see FIG. 12). Thecentral portion 40 is convexly curved in a vertical plane as shown inFIG. 11 to follow the general contour of the heel cord and lower aspectof the calf. The wing portions 42 protect the ankle at opposite sides ofthe heel cord.

The bottom tread portion 12 is shaped as indicated in FIG. 9. It iscomposed of a flexible, compressible sheet 46 which may be of the samematerial and softness as the sheet 20, and a flexible cover sheet 48secured to one side of the sheet 46. Sheet 48 may be formed of the samematerial as sheet 22 and may be heat-bonded to sheet 46 or adheredthereto by a suitable adhesive. Both sheets 46 and 48 are cut to thesame configuration.

The bottom tread portion 12 is stitched to the lower margin of the mainbody portion 10 of the boot where indicated at 50 with the cover sheeton the outside and the cushion sheet on the inside of the boot.

The insole 14 is shaped as shown in FIG. 7. It is composed of aflexible, compressible sheet 52 which may be of the same material andsoftness as the sheet 20, and a flexible cover sheet 54 secured to oneside of the sheet 52. Sheet 54 may be formed of the same material assheet 22 and may be heat-bonded to sheet 52 or adhered thereto by asuitable adhesive. A sheet 56 of cardboard or like material which issomewhat flexible (but substantially less flexible than sheets 52 and54) is secured to the opposite side of sheet 52 as by an adhesive. Thesheets 52, 54, and 56 are cut to the same configuration which isgenerally similar to that of the bottom tread portion 12.

Insole 14 is inserted in the boot with the cardboard side down. Theinsole may remain loose, but preferably the cardboard side is secured tothe sheet 46 of the bottom portion 12 by a suitable adhesive.

The boot provides a complete protective cover for the foot and calfportion of the leg of a patient, the leg-receiving part 34 beingdimensioned to extend up to about the junction of the lower and middlethird of the calf.

The boot is open along a continuous parting line defined by theconfronting edges 30 from the top of the leg-receiving part 34 to thebeginning of the stitching 32 at the toe of the boot. The entire lowercalf portion and foot of the patient are covered and protected by theboot, except for the small gap between the edges 30. The gap can bepractically eliminated by pulling the edges 30 together by means of theties 38. The ties may, of course, be released to permit the boot to beopened along the edges 30 for inspection purposes or to apply or removethe boot. .Iadd.The ties 38 constitute releasable fastening means forthe front of the boot to provide a connection between the confrontingedges 30. .Iaddend.

The entire inside of the boot has a complete inner lining of relativelysoft, non-allergenic material provided by the cover sheet 22 of the mainbody portion 10 and the sheet 54 of insole 14. The entire outside of theboot has a complete outer cover of the same relatively soft,non-allergenic material provided by the cover sheet 22 of the main bodyportion 10 and the sheet 48 of tread portion 12. The sheet 22 alsocovers the top edge of the leg-receiving part 34 of the boot. Theoutside contour of the boot is smooth and free of sharp edges or cornersto prevent injury to the patient's other extremity.

The boot provides a complete double layer of the isothermicheat-insulating material of which the sheets 20, 46, and 52 are made forthe purpose of preventing, as much as possible, the dissipation of heatfrom the foot and lower leg while at the same time permitting breathingand evaporation. These soft layers of heat-insulating material alsoprotect the foot and lower leg from trauma. It will be appreciated thatthe weight-bearing surface of the extremity of the patient when lyingdown will be over the heel cord and the lower aspect of the calf and theweight will be supported over a large area by the layers 37 of theheat-insulating material as well as the body 16 of weight-bearingmaterial (see FIG. 11). Thus the unit pressure on the back of the lowerleg of the patient is minimized.

I claim: .[.1. An isothermic protective boot having a foot-receivingpart and a contiguous leg-receiving part adapted to extend up to atleast the lower portion of the calf of a patient, said boot having acomplete inner lining of relatively soft, non-allergenic material, saidboot also having a layer of relatively soft, flexible, compressibleisothermic protective material throughout the full extent of both itsparts and a body of weight-bearing material along at least a portion ofthe back of said leg-receiving part in a position to extend along theheel cord of the wearer such that when the wearer is lying on his backthe weight-bearing surface of the extremity of the wearer will be overthe heel cord and lower aspect of the calf and not the bottom of theheel..]. .[.2. An isothermic protective boot as defined in claim 1,wherein said boot has a complete outer cover of a relatively softmaterial..]. .[.3. An isothermic protective boot as defined in claim 2,wherein said inner lining and outer cover for the leg-receiving part andthe top and sides of said foot-receiving part are portions of a singlesheet integrally joined at the top of the leg-receiving part..]. .[.4.An isothermic protective boot as defined in claim 1 or 2, wherein saidisothermic material is expanded polyurethane..]. .[.5. An isothermicprotective boot as defined in claim 1, wherein said inner lining is madeof paper..]. .[.6. An isothermic protective boot as defined in claim 3,wherein said single sheet is made of paper..]. .[.7. An isothermicprotective boot as defined in claim 1, wherein said body ofweight-bearing material is flexible and compressible but firmer thansaid layer of isothermic material..]. .[.8. An isothermic protectiveboot as defined in claim 7, wherein said weight-bearing material isexpanded polyurethane..]. .[.9. An isothermic protective boot as definedin claim 1, including an insole disposed inside the boot at the bottomand comprising a layer of said isothermic material with a portion ofsaid inner lining on its upper surface..]. .[.10. An isothermicprotective boot having a foot-receiving part and a contiguousleg-receiving part adapted to extend up to the junction of the lower andmiddle third of the calf of a patient, said boot having a complete innerlining of a relatively soft, non-allergenic material, said boot havingan outer cover of a relatively soft material, said boot also havingbetween said inner lining and outer cover plural layers of relativelysoft, flexible, compressible porous isothermic protective materialthroughout the full extent of both its parts, and a body of relativelysoft, flexible, compressible weight-bearing material along at least aportion of the back of said leg-receiving part between said layers ofisothermic material in a position to extend along the heel cord of thewearer such that when the wearer is lying on his back the weight-bearingsurface of the extremity of the wearer will be over the heel cord andlower aspect of the calf and not the bottom of the heel..]. .[.11. Anisothermic protective boot as defined in claim 10, wherein said boot hasa main body portion constituting the entire leg-receiving part and theside and upper portions of said foot-receiving part, a bottom treadportion constituting the bottom of said foot-receiving part and having aportion of one said layer of isothermic material with a portion of saidouter cover on its outer surface, and an insole disposed inside saidboot in overlying relation to said tread portion and having a portion ofanother said layer of isothermic material with a portion of said innerlining on its top surface..]. .[.12. An isothermic protective boot asdefined in claim 10, wherein said inner lining and outer cover for themain body portion of said boot are portions of a single sheet integrallyjoined at the top of said leg-receiving part..]. .[.13. An isothermicprotective boot as defined in claim 10, wherein said isothermic materialis expanded polyurethane..]. .[.14. An isothermic protective boot asdefined in claim 10, wherein said inner lining and outer cover are madeof paper..]. .[.15. An isothermic protective boot as defined in claim10, wherein said body of weight-bearing material is firmer than saidlayers of isothermic material..]. .[.16. An isothermic protective bootas defined in claim 15, wherein said body of weight-bearing material isexpanded polyurethane..]. .[.17. An isothermic protective boot asdefined in claim 11, wherein said insole has a layer of cardboard on thebottom..]. .[.18. An isothermic protective boot having a foot-receivingpart and a contiguous leg-receiving part adapted to extend up to atleast the lower portion of the calf of a patient, said boot having aninner lining of relatively soft, non-allergenic material, and a body ofweight-bearing material along at least a portion of the back of saidleg-receiving part in a position to extend along the heel cord of thewearer such that when the wearer is lying on his back the weight-bearingsurface of the extremity of the wearer will be over the heel cord andlower aspect of the calf and not the bottom of the heel..]. .Iadd.19. Anisothermic protective boot having a foot-receiving part and a contiguousleg-receiving part adapted to extend up to at least the lower portion ofthe calf of a lower extremity of a patient, said boot having a completeinner lining of relatively soft, non-allergenic material, said boot alsohaving a layer of relatively soft, flexible, compressible isothermicprotective material throughout the full extent of both its parts, a bodyof flexible, compressible weight-bearing material along at least aportion of the back of said leg-receiving part in a position to extendalong the heel cord of the patient such that when the patient is lyingon his back the weight-bearing surface of the extremity of the patientwill be over the heel cord and lower aspect of the calf thus relievingthe bottom of the heel of any substantial weight bearing, said bootbeing sufficiently flexible to afford the patient at least limitedambulation, the exterior of said boot being soft and devoid of hardsurfaces and sharp edges to preclude injury to the patient's otherextremity, said boot having confronting edges at the front permittingsaid boot to be opened along said confronting edges to apply and removesaid boot, said boot being adapted to cover and protect the lower calfportion and foot of the patient from the rear of the boot around thesides thereof to said confronting edges at the front of the boot, andreleasable fastening means for the front of said boot adapted to providea connection between said confronting edges. .Iaddend. .Iadd.20. Anisothermic protective boot as defined in claim 19, wherein said boot hasa complete outer cover of a relatively soft material. .Iaddend..Iadd.21. An isothermic protective boot as defined in claim 20, whereinsaid body of weight-bearing material is contoured to precludeconcentrations of pressure, especially adjacent the heel. .Iaddend..Iadd.22. An isothermic protectve boot as defined in claim 21, whereinsaid body of weight-bearing material is between said layer of isothermicprotective material and said outer cover, whereby the weight of theextremity is supported over a large area by said layer and body so thatunit pressure on the back of the leg is minimized. .Iaddend. .Iadd.23.An isothermic protective boot as defined in claim 22, wherein said bodyof weight-bearing material is separate from and firmer than saidisothermic protective material. .Iaddend.